outbreaks

Managing Pests With Cover Crops | Earth Wise

May 18, 2022 By EarthWise Leave a Comment

The use of pesticides in global agriculture brings with it many problems including the killing of non-target, beneficial species as well as reversing pest-management gains from the use of conservation agriculture methods.

In a newly published study by researchers at Penn State University, the use of plant cover, such as cover crops, was shown to potentially be more effective at reducing pest density and crop damage than the application of insecticides without the downsides. Cover crops reduce insect pest outbreaks by increasing pest predator abundance.

Cover crops are plantings that are primarily used to slow erosion, improve soil health, enhance water availability, smother weeds, and help control pests and diseases. Typical cover crops include mustard, alfalfa, rye, clovers, buckwheat, and winter peas. Most cover crops are fairly inexpensive to plant.

Plant cover can provide habitat for populations of natural enemies of pests. Winter cover crops can harbor pest predator populations outside of the growing season of the cash crop. When the cover crop is killed off to allow the growth of the cash crop, residues of the cover crop remain on the soil during the growing season, so they still enhance the habitat for pest predators.

Conservation agriculture includes methods like cover crops, no-till planting, and crop rotation. The use of cover crops constitutes a form of preventive pest management that is an alternative to planting seeds treated with systemic insecticides to control early-season pests. There is also the possibility for integrated pest managements, which is an approach in which insecticides are applied but only when pest numbers exceed economic thresholds despite the use of nonchemical tactics.

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Cover crops more effective than insecticides for managing pests, study suggests

Photo, posted August 8, 2011, courtesy of USDA NRCS Montana via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

COVID-19 And The Wildlife Trade | Earth Wise

December 17, 2020 By EarthWise Leave a Comment

Historically, many diseases have jumped from animals to people with serious consequences for the human host. In fact, coronaviruses alone have caused outbreaks in humans three times in the past 20 years: SARS, MERS, and COVID-19. The majority of human pathogens that caused substantial damage to human health and economies during the past three decades have originated from wildlife or livestock.

According to a team of researchers from the University of Göttingen and other international institutions, more epidemics from animal hosts are inevitable unless urgent action is taken. In order to help protect against future pandemics, which could be even more severe than the current one, the researchers published a series of suggestions for governments to consider in the journal Trends in Ecology & Evolution.

The research team calls for governments around the world to establish effective legislation to do three things: address the wildlife trade, protect habitats, and reduce the interaction between people, wildlife, and livestock.

The wildlife trade and habitat fragmentation both facilitate disease outbreaks by increasing the potential for contact between humans and animals. Animals in wildlife markets are often kept in crowded and unsanitary conditions, which creates fertile breeding grounds for pathogens to jump to humans. Animals and humans are also forced closer together when natural habitats are cleared or otherwise fragmented in order to meet the various needs of a growing global population.

Since the Covid-19 outbreak, China, Vietnam, and South Korea have introduced regulations to better manage the wildlife trade as well as support wildlife conservation. According to the researchers, these actions serve as examples for other countries to consider. The status quo isn’t good enough.

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COVID-19 highlights risks of wildlife trade

Photo, posted August 23, 2010, courtesy of the U.S. Fish and Wildlife Service Northeast Region via Flickr. Photo credit: Rosie Walunas/USFWS.

Earth Wise is a production of WAMC Northeast Public Radio.

Disease On Coral Reefs

February 19, 2019 By EarthWise Leave a Comment

The warming oceans have led to bleaching events in coral reefs around the world, but bleaching is not the only problem corals face. Disease outbreaks are also becoming more frequent, severe, and widespread.

Many factors are contributing to the problem, including pollution and nitrogen runoff from fertilizers and coastal sewer and septic systems. However, the key culprit is likely the steadily increasing ocean temperatures, which are the cause of coral bleaching. Elevated water temperatures can cause coral polyps to expel the algae that sustains them and gives them color.

According to scientists, bleaching makes corals more susceptible to illness. In the Caribbean, a coral disease hotspot, about 80% of coral cover has disappeared, largely from outbreaks of “white band disease”, so called because of a white band of dead tissue that forms in affected corals. Two crucial reef-building species, elkhorn and staghorn coral, are now nearing extinction in the regions. The reef extending along the Florida coastline is the third largest reef ecosystem in the world and nearly 35% of it has been lost to disease.

Estimates are that disease outbreaks have wiped out at least 6% of the corals on the Great Barrier Reef in Australia. In that region, diseases are more prevalent in areas where corals were damaged by fishing and other human activity because wounded coral provides an entry point for pathogens and bacteria.

In the face of climate change and mounting disease outbreaks, scientists are scrambling for solutions to stave off catastrophe. Assisting the migration of hardier coral species and breeding so-called “super corals” are among the strategies being pursued. It is unknown whether these and other forms of intervention can be used on a wide enough scale to really make a difference.

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As Disease Ravages Coral Reefs, Scientists Scramble for Solutions

Photo, posted November 29, 2012, courtesy of Robert Linsdell via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Carbon And North American Forests

September 24, 2018 By EarthWise Leave a Comment

Researchers have for the first time calculated the capacity of North American forests to sequester carbon. The detailed analysis by UC Santa Cruz and collaborators in China and Arizona considers two key factors: the natural process of forest growth and regeneration, and effects brought about by climate change.

Mapping Emerging Infectious Diseases

July 12, 2016 By WAMC WEB

Ebola. Hantavirus. Lyme disease. What do they have in common? Like most emerging infectious diseases, they originated in mammals. So many debilitating pathogens make the jump from wildlife and livestock to humans, yet at the global scale little is known about where people are most at risk of outbreaks.

Big Data + Technology = Improved Global Health

June 20, 2016 By WAMC WEB

Scientists are calling for the creation of a global early warning system for infectious diseases. Such a system would use computer models to tap into environmental, epidemiological, and molecular data – gathering the intelligence needed to forecast where disease risk is high and what actions could prevent outbreaks or contain epidemics.